Pumping jack



Jan. 15, 1952 s, c, KYLE 2,582,836

PUMPING JACK Filed Dec. 4, 1946 54 72 can/rd Vail/e INVENTOR. jamue/ CT /g/f.a

Patented Jan. 15, 1952 PUMPING JACK Samuel C. Kyle, Berkeley, Calif., assigner to The Pelton Water Wheel Company, San Francisco, Calif., a corporation of California Application December 4, 1946, Serial No. 713,890

l The invention relates to pumping jacks especially for use in extracting oil from wells which are of necessity pumped and is particularly concerned with a pumping jack of the type shown in the co-pending application of Fred H. Rued, Serial No. 667,717, iiled May 6, 1946, now Patent Number 2,481,623, and entitled Pumping Jack, The Rued application is assigned to the assignee of the present application.

In a pumping jack of this character there is provided a cylinder usually arranged vertically over the well and within which operates a piston connected through its piston rod to the polish or` sucker rod of the pump which is disposed at a depth within the well. The pumping jack piston is raised and lowered in 'a carefully regulated fashion by means of an actuating uid, usually oil, pumped into and outlof the jack cylinder under the driving force of an engine or motor and precisely controlled so that the well pump is appropriately stroked and so that the rate of pumping desired is maintained for protracted periods. In the operation of a pumping jack of this kind the viscosity and some of the other characteristics of the actuating iiuid vary from summer to Winter and furthermore there are some variations in the length of the sucker rod in any given well or in successive wells in the event the same jack is utilized repeatedly on different installations. The variabilities mentioned are difiiculties to be overcome in the design and operation of a universally applicable pumping jack.

- It has been proposed heretofore, as shown in the Rued application, to provide a conduit extending from the jack cylinder at one'side of or beneath the piston for conducting the pressure existing in the cylinder to a control valve for regulating the piston stroke. It has also been customary to employ a check valve for the purpose of preventing retrograde flow in such conduit, but considerable diiliculty has resulted in practice due to a surge or hammer occurring in that conduit due to the sudden imposition on the conduit and check valve of a relatively high pressure. This has rendered the operation of the check valve erratic and especially has rendered the operation of the control valve erratic. This condition is likely to result in a failure of the piston arresting mechanism so that the piston l can upon occasion overtravel suiliciently to cause mechanical damage not only to the pumping jack, but more seriously to the pump itself.

It is therefore an object of the invention to provide means for regulating the vlength of stroke 5 Claims. (Cl. 121-158) in a pumping jack to compensate for variations in actuating fluid viscosity especially those due to the seasons.

It is another object of the invention to provide a means of adjusting or regulating a pumping jack to cooperate properly with the particular pump with which it happens to be installed at any time.

Another object of the invention is to provid means of avoiding or preventing hammer or surge in a control line. c

An additional object of the invention is to provide means for preventing chattering or erratic operation of a check valve or control valve actuated by the hydraulic jack itself.

An additional object of the invention is to provide means for precluding damage to the pump and if possible to the pumping jack itself in the event the control structure fails to arrest the motion of the piston adjacent one end of its stroke.

Other objects of the invention together with the foregoing are attained in the embodiment of the invention disclosed in the accompanying drawings in which Figure'l is a diagrammatic disclosure of a pumping jack constructed to incorporate the present invention, certain portions of the diagram bearing legends so that it can be compared with the drawings in the copending application of Rued above identified.

Figure 2`is a cross section showing in detail a check and stop valve and connections utilized in connection with the structure of Figure-l.

Figure 3 is a cross section on a central or'axial plane showing the interior construction of the pumping jack cylinder and piston adjacent one end thereof, the structure being that diagram'- matically shown near the bottom of Figure 1.-

In its preferred form, the pumping jack ofmy invention incorporates a cylinder havingY a pis-- ton reciprocable therein under the influence of an actuating uid admitted to the cylinderto one side of the piston and incorporates a plurality ofl branch pipes communicating with the cylinder at selected, spaced locations traversed by the piston and merging into a pipe extending to a control valve for regulating the stroke of the piston. Included in the branch pipes are check valves for preventing flow of pressure iiuid from the cylinder toward the control valve and also operable to block or to prevent iiow in either direction between the cylinder and control valve. Further, there is included a means for utilizing the cylinder and piston structure as a dash pot found al'satisfactory comercial embodiment as.

shown herein.A rIhere is provided a pumpingv jack cylinder 6 of considerable vertical extent having a base frame 1 connected by struts 8 to a.

suitable support on and surrounding a Well..bore.

(not .'shown). The base 1 includes a packing structure 9 surrounding a pclishrod IIV extend@ ing downwardly into the well.' where iti-is'con.-

nected to a pump in the customary fashion; At its upper end, the rod I I is connected.. to a piston..

I2 reciprocable within the cylinder 6 and'at its lower end provided with a reentrant porticnde.- fining a cavity I3. A restricted passageway I4 ifs-afforded by a bore. through the. sidev Wall of. the piston and establishes. communication be.- tween the cavity I3 and the exterior ofthe piston when the bore is in line with a port` I6 formed in the base 1. The port IISY is connected to a. conduit I1 extending toa main valve I8.eifective to control the ingress of actuating uid tothe cylinder 6 on one side of or below the piston I2. and in timed relationship to control. the egress of theactuating fluid .from the cylinder. 6. With the timed ingress to and egress from. the cylinder 6. of the actuating fluid, the piston I2v rises and falls together with. the rod I I. In-the event of failure of any of the control instrumentalities which regulate the operation. of the piston, and in any event when the entire weightof the pump and rod structure is suddenly. imposed uponthe piston I2. without the customary regulation,v the piston descendsuntil its lower edge I8I overrides the port I6 thereby trapping a quantity of the working iluid in the cavity I3. The piston1and connections are immediately arrested and can descend to the bottom no faster than ispermit.- ted bythe expulsion of the working uid at a predetermined rate through thepassage I4. This is so slowly that nc damage. can ensue. to the structure.

For, normal operation, the regulating mecha-V nisms. create an alternate ow of actuating uid into and outof the cylinderso-thatlthe piston I-2 rises and falls with a regular rhythm. Abovethe piston, the cylinder 6 is providedwith an overow or discharge chamber 2| ofan enlargedform openinginto the cylinder Bthrough-apertures` 22 inorder to-preclude unduecompressionr above the piston. of atmospheric air. The chamber 2l. is incommunication through. a conduit. 23 with a scavenge pump or lscavengerchamber (not shown). there being provided a checkyalve 24 affording ow in thedirection of the arrowy indicated thereon,4 that is.,in a direction awayl from or. out ofthe'cylinder 6 and precluding any return flow..

To regulate theupperl limit of the pistonstroke a plurality. of pipesvsuch asv 26 intersect the.cy1.

and in general is eiective to regulate the ow of actuating fluid into and out of the cylinder 6. A check Valve 36 is interposed in the line between the pipes 33 and 34 to permit ilow away from the cylinder toward the control valve but to prevent return ow therefrom. When the piston I2 is lifted by the. pressure actuating uid above the one; off the.l ports 21 that'hasbeenselected by the valve 29, the pressure ofthe fluidis then communicated through the pipe 26, the valve 29 and the check valve 36 to the control valve toreverse theoperation of the structure. By manipulating thevalve 29 properly the desired height of stroke canbeobtained;v

Ina somewhatcomparable fashion I provide in accordanceY-withmy. invention a plurality of ports 4I.,.4243, 44and 45 at convenient, selected 1ocations in the cylinder 6. All of the ports are traversed by the piston I2 and each of them is provided with one of a plurality of pipes 41, 48, 4950 and 5I all 0f which. merge into apinc-53. This latter pipe establishes. communication.v with apipe 54- extending tothe control valve 55 for regulating the. flow of actuating. uid intoand out of the. cylinder. 6. through the. port. I6. For. convenience allfof the pipes 41, 48, 49, 5-and.5.I, as well as,.the.pipes,53.and 5.4.are referredto col.- lectively. herein as afconduit."

In accordance with theinventioneach of.- the.

pipes, for` example the pipe.- 4]-, is provided with a. Special. check.` valve. such as. the valve. desig.- nated.56. The valve. includes avalve body. 6l.' (Figure 2) having a. central. cylindricahbore?. withinwhicha valve.I thimble 63 is slidably dis.. poised..V The valve thimbleintermediate its. ends has. a. puppet.A head 64. engageablewith apoppet seat. 65,. in the valve body.. When seated.. the thimble. precludes flow past. the seat. Normal4 ly the thimble is. urgedonto. theseat by a. coil spring. 66 surrounding. an extended stem 6,1 on the, thimble and. likewise in abutment with a., plug. 6B.screwed into.the threadedendeaof the valve body.

The-valve thimbleis. centrally provided with a bore. 1|. from. which a plurality of passagesy 12. established communication between the interior. of. the valve. thimble andi the. exterior thereof when the valve is unseatedv against. the.. compres.- sive. urgency of the spring 66...

Extendingy into one side of the val'vebody` 6J above or to. one. side. of the seat. 65 is a short' nipple. 13. also screwed into the. cylinder 6. in communicationv with. the port 4I, for example, and settingv up. communication between. such cylinder and theinterior, chamber 1.4..ononeside of.the.va1ve seat.6.5. The nipple 13.constitutes or. representsthe pipe 4-1. Likewise. screwed in.- to.l thevvalvebody IiIA` are fttirus-v 16 and-1.1 ineluded-,in or. portionscf the pipe 53.V

In the.- opera-tion of the structure as soffarfdefscribed.l when thev pistonY I2'. rises abovefthe port 4I forvexample. pressure fiuid exerts its force through the pipev 411. (represented by thenipple 13)y and imposes a force upon the head: 6ftY ot the checkvalve to augment thepressurezof. the. spring 6.6i so' that the: valve isv held seatedz and: communication therethrough isprecluded; Howlever when the piston I2 descends-below. the portV 4I? and permitsv atmospheric, or a. relatively low pressure fromy the chamber 2J orv from the conf duit 23 to be imposed'. throughthe, pipe:4f1 (the nipple'13) upon the spring. Side of the: check valve, thenthe pressure fluidalready present'zinV the conduitI 541s eiectivc. to: unseat the'check valve against .the urgency; oi the. spring.. The

resulting sudden reduction of pressure in the control valve conduitI 54 is effective to actuate the control instrumentalities and reverse the previous flow direction of the actuating fluid. The result is that the piston no longer descends but rather is again supplied on its under side with actuating fluid and is again lifted. By this means the check valve is effective in the structure to regulate the bottom stroke limit of the jack piston. It is emphasized that the check valve is installed in the conduit extending to the control valve at a location as close as possible to the cylinder port such as the port 4I. 'Ihat is, the nipple I3 is a short pipe so that pressure variations therein are not effective to set up surges or water hammer or similar violent phenomena and consequently the control valve operates smoothly. Previously, fluid surge in the control conduit produced sundry difficulties. In accordance with the present invention the check valve is installed close to the main cylinder so that violent surging is precluded.

Also in accordance with the invention, I provide means for selecting any one of the ports for operation while precluding operation of the remaining ones. The blocking means for preventing operation of the various ports 4I, 42, 43, 44 and 45 can take any suitable form such as an additional valve, but preferably I utilize the check valve shown in Figure 2 and add to it a threaded stem 8l engaging the plug 68 and rotatable by means of a tool engaged with an end slot 82 to approach the head 61 of the check valve. The stem 8l not only regulates the extent of opening of the check valve, but if suinciently actuated is effective forcibly to hold the check valve on its seat thus to preclude fluid flow therethrough in either direction. The stem 8| when in appropriate position is locked by a nut 83 jammed against the plug 68 and also by a cap nut 84 for sealing the structure against tampering.

With the structure described, any one of the check valves 56 can be opened to afford unidirectional flow without surge or Water hammer and thereby to select the point of reversal or bottom stroke limit of the piston I2 in accordance with whichever port 4|, 42 etc. is opened by such operation. The other or non-selected check valves are held completely closed by a suitable adjustment of the stem 8| so that the structure is set for the stroke operation desired. With this arrangement, stroke changes can be made periodically throughout the season to take care of variations between summer and Winter .f

fluid viscosity. Also there can be established appropriate adjustments if or when the pumping jack is moved from one installation to another. Furthermore, the installation is such that water hammer or surging or chatter is prevented and not only does the acting check valve have a long life but the control valve is provided with a smooth impulse and not a repetitive deleterious one. Finally, in the event of failure of the structure to act as a bottom limit of the stroke, the mechanism is not damaged because the dash pot effect of the piston and cylinder at the bottom is effective gradually to permit the structure to come to mechanical rest.

I claim:

1. A pumping jack comprising a cylinder, a piston reciprocable in said cylinder, means for supplying said cylinder with actuating fluid, a hydraulically actuated control valve for said supplying means, a relatively long hydraulic actuation conduit extending between said cylinder and said control valve, and a check valve closed by flow of actuating fluid from said cylinder disposed in said conduit between said cylinder and said valve and located close to said cylinder.

2. A pumping jack comprising a, cylinder, a piston reciprocable in said cylinder, means for admitting pressure fluid to said cylinder beneath said piston, a control valve for said pressure uid, a conduit including a pipe extending to said control valve, and a plurality of branch pipes connected to said pipe and opening into said cylinder at spaced locations traversed by said piston, check valves closed by said pressure uid within said cylinder disposed in said branch pipes adjacent said cylinder, and means for mechanically holding said check valves in closed position to close said branch pipes.

3. A pumping jack comprising a cylinder, a piston reciprocable in said cylinder, means for admitting actuating uid to said cylinder on one side of said piston, a control valve for said actuating uid, a conduit extending to said control valve and opening into said cylinder in a location traversed by said piston, a check valve in said conduit between said control valve and said cylinder and responsive to flow of actuating fluid from said cylinder through said conduit for blocking flow through said conduit of said actuating iiuid from said cylinder, and means for mechanically holding said check valve closed for completely blocking ow of said actuating fluid through said conduit.

4. A pumping jack as in claim 3 in which the check valve is disposed closely adjacent the cylinder.

5. A pumping jack comprising a cylinder, a piston reciprocable in said cylinder, means for admitting pressure fluid to said cylinder on one side of said piston, a control valve for said pressure iiuid, a conduit extending to said control valve and communicating with said control valve and communicating with said cylinder in a selected one of several locations traversed by said piston, and a check valve closed by said pressure fluid Within said cylinder disposed in said conduit adjacent said location for blocking flow of said pressure iiuid from said cylinder through said conduit.

SAMUEL C. KYLE.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,185,448 Suter Jan. 2, 1940 2,287,709 Ringman June 23, 1942 

